In recent years, mobile phones are provided with various capabilities in addition to the communication function, such as e-mail transmission/reception, digital camera shooting, recording/reproducing, television reception, scheduling and so on.
There is a demand to view a display part with the mobile phone folded small in using a given function out of these plural functions. In order to meet this demand, a mobile phone has been proposed which includes two pivots rotating independently of each other in a hinge portion foldably connecting a first housing including a display part and a second housing including an operation part.
For example, Patent Document 1 discloses electronic equipment in which a main body including an operation part and an overlap part including a display part are connected to each other so as to cover the operation part in non-operation state, wherein the overlap part is provided about a pivot part so as to be capable of rising and a rotatable part intersecting substantially at a right angle with the pivot is provided to allow the overlap part to be rotatable within the range of 180 degrees, whereby the overlap part can be flipped over. It is known that flipping over the overlap part of this electronic equipment can hide and expose the display part with the equipment folded compactly.
Patent Document 2 discloses a mobile phone with zoom lenses in which: a shooting lens and a plurality of zoom lenses are arranged on the central axis of a hinge portion; a liquid crystal monitor part including a liquid crystal monitor and an operation part including operation buttons are connected to each other rotatably by means of the hinge portion; and a rotating plate is provided between the hinge portion and the liquid crystal monitor part so as to be rotatable in the range from zero degree to 360 degrees. It is known that this mobile phone with the zoom lenses can shoot a self-portrait when the liquid crystal monitor part is rotated 90 degrees clockwise and can shoot another person when the liquid crystal monitor part is rotated 90 degrees anticlockwise on the rotating plate.
Patent Document 3 discloses a foldable mobile phone including a first rotation shaft for closing both the housings and a second rotation shaft intersecting at a right angle with the first rotation shaft. In this foldable mobile phone, when the display part is rotated 180 degrees and is then closed, the display part comes into sight so as to be viewed in a receiving condition without manipulation for opening/closing the housings. It is known that four direction keys and an enter key are provided at the lower part of the display part, and therefore, the user can view the display part when using these keys for playing a video game or so with the display part in the compactly closed state flipped over.
The main function of the mobile phones is making and receiving calls still. For greater portability and salability of the mobile phones, importance has been placed on downsizing and weight reduction. In view of usability, the mobile phones are oriented portrait and reduced in width.
When the liquid crystal display parts of the aforementioned mobile phones are fixed portrait, a landscape image needs to be scaled down so that the image fits in the portrait screen or the user has to scroll the image horizontally to see the whole image.
Alternatively, the landscape image may be rotated 90 degrees for showing it in the liquid crystal display part in the portrait orientation. However, in a foldable mobile phone in which the liquid crystal part and the operation part come in sight when the first housing and the second housing are opened, the operation part is also rotated 90 degrees, which means that the user sees the indications marked in the information input buttons and the like which are rotated 90 degrees and arranged in a different layout from the usual one. It is troublesome and difficult for the user to do input with the operation keys in such an unusual layout.
To solve these problems, for example, Patent Document 4 discloses a foldable mobile phone of which liquid crystal display part supported on the first housing so as to be switchable from the portrait orientation to the landscape orientation even when the foldable mobile phone itself is held portrait. The liquid crystal display part of this foldable mobile phone is supported by a support shaft arranged at the center of the liquid crystal display part vertically to the liquid crystal display part such that the liquid crystal display part is rotated 90 degrees about the support shaft.
In a foldable mobile phone in Patent Document 5, the liquid crystal display part is pivotally supported on a support part connecting the liquid crystal display part to a base part of the mobile phone main body, and a displayed content is changed according to the orientation of the display screen.
As shown in Patent Document 6, a foldable mobile phone is known which includes a support mechanism supporting the liquid crystal display part rotatably about and slidably on the first housing. In this foldable mobile phone, the liquid crystal display part is made to slide vertically and is then rotated about the support shaft provided at the center of the liquid crystal display part, thereby avoiding contact with the hinge portion and a protruding portion at the lower end of the first housing to thus increase the size of the liquid crystal display part.    Patent Document 1: Japanese Unexamined Patent Application Publication 2003-239943    Patent Document 2:Japanese Unexamined Patent Application Publication 2003-309756    Patent Document 3: Japanese Unexamined Patent Application Publication 2002-118633    Patent Document 4: Japanese Unexamined Patent Application Publication 2001-156893    Patent Document 5: Japanese Unexamined Patent Application Publication 2004-64716    Patent Document 6: Japanese Unexamined Patent Application Publication 2003-319043